The present invention relates generally to medical diagnostic systems and, more particularly, to a self contained hand-held portable instrument and an associated disposable sample container or test cell for performing a variety of real time medical diagnostic tests with respect to blood or other fluids received from humans or animals.
Electronic devices for automatically conducting a medical diagnostic test a utilizing a patient's blood or other bodily fluids in a laboratory, hospital or physician's office are generally well known. With such electronic devices, a small sample of the patient's blood or other bodily fluid is obtained by a health care professional for the purpose of conducting the analysis. In some such devices the blood or other bodily fluid is mixed with a dry or lyophilized activation reagent that is effectively re-hydrated when mixed with the blood or other fluid. The resulting fluid is then exposed to light at a particular wavelength and a photo detector receives the light signal reflected from the fluid to provide a resulting output diagnostic. Other such electronic devices function in the same, similar or different ways to obtain the desired result.
While such other prior art electronic diagnostic devices are generally effective in performing such medical diagnostic testing, such devices are often bulky and, therefore, are basically restricted to being used only in a laboratory or hospital or, in some cases, a physician's office. More recently, light weight portable devices have been developed for performing a limited number of certain individual or specific diagnostic tests. However, such more recent devices also suffer from defects including, in some cases, the ability to perform only a single diagnostic test or a single group of closely related diagnostic tests. In addition, some such more recent portable devices are structurally and/or functionally complex and relatively expensive to obtain and use. There thus exists a need for a relatively low cost, hand held, portable, self contained instrument which is capable of performing a plurality of different medical diagnostic tests with respect to individual samples of a patient's blood or other bodily fluid which is relatively inexpensive to obtain, simple and inexpensive to operate and yet, which provides an effective, consistent diagnostic quality result.
The present invention overcomes these and other problems associated with such prior art devices by providing a self contained medical diagnostic device and system which is small enough to fit in the palm of the hand of a user, but yet is programmed to perform a plurality of different medical diagnostic tests, including tests for glucose, calcium, potassium, lead, hematacrit, blood urea/nitrogen, creatinine, bilirubin, ALK phosphates and other such tests. The device and system of the present invention is also adaptable to perform standard medical urine chemistry tests and urinalysis, at least to the degree of accuracy necessary for adequate screening of controlled substances, as well as blood alcohol testing with an accuracy efficient for law enforcement use. The present medical device and system provides on the spot analysis in a very short time, usually a few minutes or less, and the results of the analysis is stored within the memory of the device for later downloading or other retrieval which improves efficiency and reduces manual record keeping. The accuracy of the results obtained using the present device/system is unaffected by the medical training, laboratory skills or lack of laboratory skills of the user. In using a device or system in accordance with the present invention, blood or some other bodily fluid is deposited into a special sample container or test cell by capillary action or a self-contained collection probe to facilitate real time reading of the results with little or no possibility of contamination due to delay, transport or the like. Because only a small amount of blood or other fluid is needed for the testing and analysis, a “finger stick” technique can sometimes be used resulting in less patient apprehension or discomfort. The analysis occurs substantially, immediately (typically within one to three minutes) resulting in little or no sample deterioration, which often occurs when samples are transported to a remotely located laboratory or other facility for analysis. A device or system in accordance with the present invention employs a special registration technique, in a preferred embodiment, using special barcoding to insure that the device or system performs the appropriate diagnostic test for the particular test cell and that the results of the test are properly stored in a manner which precludes the possibility of transposing the test results from different patients.